Exorcism of Annotation-Processing Tools

By : Budi Oktaviyan, Engineering Manager Grab
Live : https://www.youtube.com/watch?v=X2qKs6VhHMA

Transcript

1. Exorcism of annotation-processing tools Budi Oktaviyan @budioktaviyans
2. The Annotation-Processing
3. “Tools build in javac for scanning and processing annotations at compile time” -Hannes Dorfmann-
4. What annotation-processing can do ?
5. Annotation Processing • Part of javac • @Annotation based • Generate java source code files
6. Annotation Processing • Part of javac • @Annotation based • Generate java source code files
7. Annotation Processing • Part of javac • @Annotation based • Generate java source code files
8. Benefit of using annotation-processing
9. Reduce writing a boilerplate code...
10. Dependency Injection (No Framework)
11. Dependency Injection (No Framework)
12. Dependency Injection (No Framework)
13. Dependency Injection (No Framework)
14. Too much step ?
15. Using a dependency injection framework by leverage the annotation-processing tools...
16. Implementing the annotation-processing
17. Annotation Basic Implementation
18. Annotation Basic Implementation
19. Annotation Basic Implementation
20. Annotation Basic Implementation
21. Annotation Basic Implementation
22. Annotation Basic Implementation
23. Clean and build your application project...
24. Annotation Basic Implementation
25. How does the annotation-processing tools works ?
26. Java Annotation-Processing Tools
27. Kotlin Annotation-Processing Tools (KAPT)
28. Type of Annotation-Processing • Run-Time Processing • Compile-Time Processing
29. Run-Time Annotation-Processing • Run time code generation • JVM based support and “Native” java code • Using reflections method
30. Run-Time Annotation-Processing • Run time code generation • JVM based support and “Native” java code • Using reflections method
31. Run-Time Annotation-Processing • Run time code generation • JVM based support and “Native” java code • Using reflections method
32. Run-Time Annotation-Processing Libraries
33. Run-Time Annotation-Processing • Google Guice • Google Roboguice
34. Run-Time Annotation-Processing • Google Guice • Google Roboguice
35. Type of Annotation-Processing • Run-Time Processing • Compile-Time Processing
36. Compile-Time Annotation-Processing • Compile time code generation • JVM based support and “Native” java code • Without reflections method
37. Compile-Time Annotation-Processing • Compile time code generation • JVM based support and “Native” java code • Without reflections method
38. Compile-Time Annotation-Processing • Compile time code generation • JVM based support and “Native” java code • Without reflections method
39. Compile-Time Annotation-Processing Libraries
40. Compile-Time Annotation-Processing • Dagger 2 • Room • Moshi
41. Compile-Time Annotation-Processing • Dagger 2 • Room • Moshi
42. Compile-Time Annotation-Processing • Dagger 2 • Room • Moshi
43. Creating Custom Annotation
44. Custom Annotation Creation • Annotation Module • Processor Module
45. Implement the annotation module...
46. Annotation Module
47. Annotation Marker • @Target • @Retention
48. Specify which target of your custom annotation should be implemented ?
49. • TYPE • FIELD • METHOD • FUNCTION • PARAMETER • CONSTRUCTOR Annotation Marker - @Target
50. • @Target • @Retention Annotation Marker
51. Indicates how your custom annotation is stored ?
52. • BINARY/CLASS • SOURCE • RUNTIME Annotation Marker - @Retention
53. Custom Annotation Creation • Annotation Module • Processor Module
54. Implement the processor module...
55. Processing The Modules • Initialize, using the init() function • Processing, using the process() function with or without a Kotlin Poet • Qualifying names of the annotations, using the getSupportedAnnotationTypes() function • Tell compiler which java version do we use, using getSupportedSourceVersion() function
56. Processor Module
57. Processing The Modules • Initialize, using the init() function • Processing, using the process() function with or without a Kotlin Poet • Qualifying names of the annotations, using the getSupportedAnnotationTypes() function • Tell compiler which java version do we use, using getSupportedSourceVersion() function
58. Processor Module
59. Processing The Modules • Initialize, using the init() function • Processing, using the process() function with or without a Kotlin Poet • Qualifying names of the annotations, using the getSupportedAnnotationTypes() function • Tell compiler which java version do we use, using getSupportedSourceVersion() function
60. Processor Module
61. Processing The Modules • Initialize, using the init() function • Processing, using the process() function with or without a Kotlin Poet • Qualifying names of the annotations, using the getSupportedAnnotationTypes() function • Tell compiler which java version do we use, using getSupportedSourceVersion() function
62. Processor Module
63. Using Custom Annotation
64. Custom Annotation
65. Processing Rounds
66. Annotation-Processing Rounds
67. Limitations
68. Annotation-Processing Limitations • Reflection inspect or access existing object (Not create a new ones) • Processing rounds on Run-Time (First initialization) issue • Processing rounds on Compile-Time (Build-Time) issue • Annotation-Processor is not debugable or testable • Not supporting multiple processing rounds (KAPT)
69. One more thing...
70. Kotlin Symbolic Processing (KSP)
71. Why KSP ? • Challenge to make build speed faster (Compile-Time) • APT/KAPT slow on Compile-Time (Build-Time) • Kotlin does not have a “Native” annotation-processing system • Offers powerful and simple API to parse Kotlin code directly • Claim 2x faster than KAPT (Build-Time)
72. KSP - Getting Started
73. Getting Started
74. Getting Started
75. KSP - Processing Modules
76. Processing KSP Modules • Initialize, using the init() function • Processing, using the process() function • Generating, using the finish() function
77. KSP Module
78. Processing KSP Modules • Initialize, using the init() function • Processing, using the process() function • Generating, using the finish() function
79. KSP Module
80. Processing KSP Modules • Initialize, using the init() function • Processing, using the process() function • Generating, using the finish() function
81. KSP Module
82. KSP - Downside
83. Symbolic-Processing Downside • Minimum IDE or tooling support • Multi-Module are not yet supported • Questioning of faster Compile-Time (Build-Time) • Experimental supported for Room and Moshi • Dagger and Hilt are not yet supported
84. Reference • https://hannesdorfmann.com/annotation-processing/annotationprocessing101 • https://iammert.medium.com/annotation-processing-dont-repeat-yourself-generate-your-code-8425e60c6 657 • https://medium.com/swlh/all-about-annotations-and-annotation-processors-4af47159f29d • https://medium.com/@workingkills/pushing-the-limits-of-kotlin-annotation-processing-8611027b6711 • https://android-developers.googleblog.com/2021/02/announcing-kotlin-symbol-processing-ksp • https://medium.com/@jsuch2362/my-first-kotlin-symbol-processing-tool-for-android-4eb3a2cfd600 • https://kennay-kermani.medium.com/kotlin-symbol-processing-speeds-up-your-android-build-process-707 9ff0bff07 • https://www.zacsweers.dev/kotlin-symbol-processor-early-thoughts